[2] For compliance reasons, certain CA systems must conduct a Key Ceremony before issuing any Digital Certificates. Trust Centres and Government projects are two examples where a key ceremony may be required in order to comply with local laws or international standards.
Links:
[1] http://www2.digi-sign.com/compliance/key%20ceremony/index
[2] https://www.digi-sign.com/downloads/download.php?id=digi-ca-admin-pdf